Not exactly, but sort of!
The definition of cuckold is simply: a man whose wife engages in sex with other men.
This could be with or without his knowledge. Simple enough until people start applying little nuances to it.
Many couples enjoy having threesomes and moresomes with memebers of various sexes and are usually considered "Swingers".
If they restrict their threesome/moresome activities to only the wife having other partners, they then may be considered a "Hot Wife" couple wherein the husband enjoys sharing his wife sexually with other men, often having threesomes, but maintaining an equal standing with his wife or he may be dominant to her.
Today's generally accepted meaning of cuckolding is that where the wife is the sexually dominant half of the marriage and enjoys sex with others beside her husband, often with his knowing and condoning it. She may allow him to participate in a threesome, but more often, she will simply enjoy sex with her lover by themselves.
Some cuckolds are permitted to watch, masturbate and even take photos or videos.
Many cuckold couples are also in Female Dominant relationships.
The term has also been altered in many circles to include unmarried couples as well, although this is technically incorrect.
So as you can see, cuckolding can mean various thing to different people.
Don't worry yourself too much about the terms, You'll figure it out as you go along.
Just find out where you and your wife fit comfortably and enjoy!